Stent for endoluminal delivery of active principles or agents

Abstract

The present invention provides a stent for implantation at a site within a human or animal body comprising: an expandable body having an inner surface and an outer surface; and treatment agents applied to the outer surface of the expandable body, the treatment agents comprising a combination of Paclitaxel and FK506 or their derivatives or analogues.

1 . A stent for implantation at a site within a human or animal body comprising:
 an expandable body having an inner surface and an outer surface; and   treatment agents applied to the outer surface of the expandable body, the treatment agents comprising a combination of Paclitaxel and FK506 or their derivatives or analogues,   wherein the treatment agents are present in a Paclitaxel:FK506 weight ratio in the range from 1:72 to 1:0.2, and   wherein the treatment agents have been loaded onto the outer surface of the expandable body in a powder or paste form and subsequently the loaded treatment agents have been stabilized by a stabilization treatment selected from:   exposure to temperature or thermal cycles;   immersion in solvent;   exposure to solvent sprays;   exposure to solvent vapors;   treatment with laser;   application of an adhesive protective coating; and   lyophilization.   
     
     
         2 . The stent according to  claim 1 , wherein the outer surface of the expandable body includes formations for receiving the treatment agents. 
     
     
         3 . The stent according to  claim 2 , wherein the formations comprise cavities having an opening towards the outer surface of the expandable body. 
     
     
         4 . The stent according to  claim 1 , wherein the expandable body is formed by elements defining a reticular structure. 
     
     
         5 . The stent according to  claim 4 , wherein the outer surface of the expandable body includes formations for receiving the treatment agents, the formations being present on the elements. 
     
     
         6 . The stent according to  claim 1 , wherein the weight ratio is in the range from 1:18 to 1:0.2. 
     
     
         7 . The stent according to  claim 1 , wherein the weight ratio is in the range from 1:8 to 1:0.5. 
     
     
         8 . The stent according to  claim 1 , wherein the weight ratio is in the range from 1:2 to 1:0.7. 
     
     
         9 . The stent according to  claim 1 , wherein the weight ratio is in the range from 1:3 to 1:1. 
     
     
         10 . The stent according to  claim 1 , wherein the treatment agents are present in a total quantity in the range between 50 and 1000 micrograms. 
     
     
         11 . The stent according to  claim 10 , wherein the total quantity is in the range between 70 and 700 micrograms. 
     
     
         12 . The stent according to  claim 10 , wherein the total quantity is in the range between 140 and 500 micrograms. 
     
     
         13 . The stent according to  claim 10 , wherein the total quantity is in the range between 200 and 400 micrograms. 
     
     
         14 . The stent according to  claim 1 , wherein Paclitaxel is present in a quantity by weight of at least 25 micrograms. 
     
     
         15 . The stent according to  claim 14 , wherein Paclitaxel is present in a quantity by weight of at least 80 micrograms. 
     
     
         16 . The stent according to  claim 1 , wherein FK506 is present in a quantity by weight of at least 60 micrograms. 
     
     
         17 . The stent according to  claim 16 , wherein FK506 is present in a quantity by weight of at least 135 micrograms. 
     
     
         18 . The stent according to  claim 2 , wherein the formations for receiving comprise cavities and wherein the cavities contain a homogeneous mixture of the treatment agents. 
     
     
         19 . The stent according to  claim 2 , wherein the treatment agents are arranged in a layered structure in the formations comprising at least two layers. 
     
     
         20 . The stent according to  claim 19 , wherein the layers are homogeneously constituted by one of the treatment agents or by a mixture of the treatment agents. 
     
     
         21 . The stent according to  claim 19 , wherein the layered structure includes an associated layer comprising at least one of a polymeric material and an excipient substance. 
     
     
         22 . The stent according to  claim 21 , wherein the associated layer is situated in an internal position of the layered structure. 
     
     
         23 . The stent according to  claim 21 , wherein the associated layer is situated in a position external to the layered structure. 
     
     
         24 . The stent according to  claim 1 , further comprising a top coat applied to the outer surface comprising one of the treatment agents or a mixture of the treatment agents. 
     
     
         25 . The stent according to  claim 2 , wherein the formations for receiving comprise cavities having a substantially step-like profile. 
     
     
         26 . The stent according to  claim 1 , further comprising pharmacologically acceptable excipients/additives which are added to the treatment agents. 
     
     
         27 . The stent according to  claim 1 , wherein the treatment agents comprise a combination of Paclitaxel and FK506. 
     
     
         28 . The stent according to  claim 27 , wherein the combination of Paclitaxel and FK506 is present in a total quantity comprised in the range between 50 and 1000 micrograms. 
     
     
         29 . The stent according to  claim 28 , wherein the total quantity is comprised in the range between 70 and 700 micrograms. 
     
     
         30 . The stent according to  claim 28 , wherein the total quantity is comprised in the range between 140 and 500 micrograms. 
     
     
         31 . The stent according to  claim 28 , wherein the total quantity is comprised in the range between 200 and 400 micrograms. 
     
     
         32 . The stent according to  claim 27 , wherein Paclitaxel is present in a quantity by weight of at least 25 micrograms. 
     
     
         33 . The stent according to  claim 32 , wherein Paclitaxel is present in a quantity by weight of at least 80 micrograms. 
     
     
         34 . The stent according to  claim 27 , wherein FK506 is present in a quantity by weight of at least 60 micrograms. 
     
     
         35 . The stent according to  claim 34 , wherein FK506 is present in a quantity by weight of at least 135 micrograms. 
     
     
         36 . A method of preparing a stent of  claim 1 , comprising:
 providing an expandable body having an inner surface and an outer surface;   providing treatment agents, the treatment agents comprising a combination of Paclitaxel and FK506 or their derivatives or analogues and the treatment agents being present in a Paclitaxel:FK506 weight ratio in the range from 1:72 to 1:0.2;   applying the treatment agents to the outer surface of the expandable body, the treatment agents being in a powder or paste form; and   subsequently stabilizing the treatment agents by a stabilization treatment selected from:   exposure to temperature or thermal cycles;   immersion in solvent;   exposure to solvent sprays;   exposure to solvent vapors;   treatment with laser;   application of an adhesive protective coating; and   lyophilization.